Roof trusses used in the building industry are usually fashioned from steel or timber, fabricated in a factory, and assembled together on-site. Such assembly usually involves connection of the roof trusses to the frame of the building through conventional fixing systems such as bolts, screws, nails or rivets. It is quite common for roof trusses to need to be fitted at an angle other than perpendicular to the wall frame.
Many styles of roofing such as hipped roofs include direct inter-connection of roof trusses. To achieve this, the first truss is usually braced into position and further roof trusses are added until the roof frame is completed and self-supporting.
However, these methods typically require the fastening of each roof truss to the wall frame at a fixed angle before the trusses can be joined together to form a roof frame. At present, tie down apparatus are fitted to the roof truss and/or wall frame at the factory and are configured in a manner which allows for the roof truss to be fitted to the wall at a single angle. Existing tie down methods are thus prone to error because if the trusses arrive at a site and the tie down apparatus is fitted, configured or orientated incorrectly, the roof truss is not able to be fitted at the required angle. Such mistakes may result in prolonged assembly times, increased labour requirements, increased manufacturing, and ultimately more expense for the manufacturer and end consumer.
The Applicant is not aware of a truss tie down apparatus which allows for the fitting a roof truss to a wall frame at any angle (including during on-site assembly), nor of a system which allows for multi-angle tie down apparatus to be factory fitted to mass produced roof and wall trusses.
In addition, at the time of assembling conventional roof truss systems, the exact angle of each truss must be precise when fastened to the frame. If it is not, the trusses may not match up at a central location correctly. It is labour-intensive and time consuming to have to calculate and ensure each angle is correct, and there is presently no scope to adjust the position of the truss once it has been secured to the wall frame.